Ben Franklin’s Kite Experiment

In June of 1752, Ben Franklin sought to prove that lightning was electrical by flying a kite in stormy weather. When Franklin touched the iron key attached to the kite’s string, he saw sparks fly between his knuckle and the metal key. But some historians doubt that this famous experiment really happened.

Code Check, a publisher of books about building and electrical codes, is not the usual educational site for middle-school students, but they feature Ben Franklin in many of their books because he "made major contributions to each of the four main disciplines of building inspection: Building, Plumbing, Mechanical, and Electrical." This page explains Franklin's famous experiment along with an overview of the Leyden jar used in the experiment. "The first device capable of storing an electric charge was the Leyden jar. Invented by a German, Ewald G. von Kleist, on November 4, 1745, he made the discovery by accident."

Because there was no eyewitness account written about Franklin's kite experiment, some historians argue that the experiment didn't occur at all, and others argue that it happened differently than described. "It doesn't really matter if Benjamin Franklin indeed performed the kite experiment in reality. What really matters is the question if this experiment (or maybe only a theoretical proposal) is founded on sound scientific principles and as a matter of fact it is a possible experiment that enables the conclusion that lightning is an electric phenomenon."

Historian Tom Tucker has his own ideas about Franklin's electrifying kite adventure, and published a book about it ("Bolt of Fate: Benjamin Franking and his Electric Kite Hoax") in 2003. Tucker argues that the experiment was originally proposed as a joke to get back at the British Royal Society because they had given a cold shoulder to his earlier electrical research. "It was his way of saying, Go fly a kite in a storm! But when his suggestion reached France, where people took it seriously, Franklin decided to play along and claimed he really had conducted the experiment."

"From a simple glass rod to an invention that still today saves lives, explore some of Franklin's electrifying discoveries and test your knowledge of electricity." This fab multimedia activity from PBS demonstrates three of Franklin's experiments, including recreating his kite experiment. Choose material for the key, various parts of the kite string, and then pick your weather conditions, and watch what happens.

Created and collected by Wright Fellow Robert A. Morse and archived at ComPADRE, this seven page PDF for high-school and college students, is just one piece of a larger project titled "Ben Franklin As My Lab Partner – Experiments in Electrostatics." Learn more about Franklin's experiments by following along with Joseph Priestley's 1775 account of it, along with related excerpts from other eighteenth-century scientists. Dr Morse concludes that given the number of times the experiment has been safely reproduced, there is no reason to doubt the accounts given by Franklin and Priestley.